fix / work around bugs in bufio test

R=r
DELTA=11  (8 added, 0 deleted, 3 changed)
OCL=15405
CL=15405

src/lib/bufio.go

@@ -291,18 +291,26 @@ func (b *BufRead) ReadLineBytes(delim byte) (line *[]byte, err *os.Error) {
 	return buf, err
 }
 
+// BUG(bugs/bug102.go): string(empty bytes array) throws error
+func ToString(p *[]byte) string {
+	if len(p) == 0 {
+		return ""
+	}
+	return string(p)
+}
+
 // Read until the first occurrence of delim in the input,
 // returning a new string containing the line.
 // If savedelim, keep delim in the result; otherwise chop it off.
 func (b *BufRead) ReadLineString(delim byte, savedelim bool) (line string, err *os.Error) {
 	bytes, e := b.ReadLineBytes(delim)
 	if e != nil {
-		return string(bytes), e
+		return ToString(bytes), e
 	}
 	if !savedelim {
 		bytes = bytes[0:len(bytes)-1]
 	}
-	return string(bytes), nil
+	return ToString(bytes), nil
 }
 
 

test/bufiolib.go

@@ -121,7 +121,7 @@ var readmakers = []*(p *[]byte) io.Read {
 func ReadLines(b *bufio.BufRead) string {
 	s := ""
 	for {
-		s1, e := b.ReadLineString('\n', false)
+		s1, e := b.ReadLineString('\n', true)
 		if e == bufio.EndOfFile {
 			break
 		}